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ext::Unicode::NorPerlzPrograemxmte:r:sUnRiecfoede::Normalize::Normalize(3p)


NAME
       Unicode::Normalize - Unicode Normalization Forms

SYNOPSIS
       (1) using function names exported by default:

         use Unicode::Normalize;

         $NFD_string  = NFD($string);  # Normalization Form D
         $NFC_string  = NFC($string);  # Normalization Form C
         $NFKD_string = NFKD($string); # Normalization Form KD
         $NFKC_string = NFKC($string); # Normalization Form KC

       (2) using function names exported on request:

         use Unicode::Normalize 'normalize';

         $NFD_string  = normalize('D',  $string);  # Normalization Form D
         $NFC_string  = normalize('C',  $string);  # Normalization Form C
         $NFKD_string = normalize('KD', $string);  # Normalization Form KD
         $NFKC_string = normalize('KC', $string);  # Normalization Form KC

DESCRIPTION
       Parameters:

       $string is used as a string under character semantics (see
       perlunicode).

       $codepoint should be an unsigned integer representing a
       Unicode code point.

       Note: Between XS edition and pure Perl edition, interpre-
       tation of $codepoint as a decimal number has incompatibil-
       ity.  XS converts $codepoint to an unsigned integer, but
       pure Perl does not.  Do not use a floating point nor a
       negative sign in $codepoint.

       Normalization Forms


       "$NFD_string = NFD($string)"
           returns the Normalization Form D (formed by canonical
           decomposition).

       "$NFC_string = NFC($string)"
           returns the Normalization Form C (formed by canonical
           decomposition followed by canonical composition).

       "$NFKD_string = NFKD($string)"
           returns the Normalization Form KD (formed by compati-
           bility decomposition).

       "$NFKC_string = NFKC($string)"
           returns the Normalization Form KC (formed by



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           compatibility decomposition followed by canonical com-
           position).

       "$FCD_string = FCD($string)"
           If the given string is in FCD ("Fast C or D" form; cf.
           UTN #5), returns it without modification; otherwise
           returns an FCD string.

           Note: FCD is not always unique, then plural forms may
           be equivalent each other. "FCD()" will return one of
           these equivalent forms.

       "$FCC_string = FCC($string)"
           returns the FCC form ("Fast C Contiguous"; cf. UTN
           #5).

           Note: FCC is unique, as well as four normalization
           forms (NF*).

       "$normalized_string = normalize($form_name, $string)"
           As $form_name, one of the following names must be
           given.

             'C'  or 'NFC'  for Normalization Form C  (UAX #15)
             'D'  or 'NFD'  for Normalization Form D  (UAX #15)
             'KC' or 'NFKC' for Normalization Form KC (UAX #15)
             'KD' or 'NFKD' for Normalization Form KD (UAX #15)

             'FCD'          for "Fast C or D" Form  (UTN #5)
             'FCC'          for "Fast C Contiguous" (UTN #5)

       Decomposition and Composition


       "$decomposed_string = decompose($string)"
       "$decomposed_string = decompose($string, $useCompatMap-
       ping)"
           Decomposes the specified string and returns the
           result.

           If the second parameter (a boolean) is omitted or
           false, decomposes it using the Canonical Decomposition
           Mapping.  If true, decomposes it using the Compatibil-
           ity Decomposition Mapping.

           The string returned is not always in NFD/NFKD.
           Reordering may be required.

               $NFD_string  = reorder(decompose($string));       # eq. to NFD()
               $NFKD_string = reorder(decompose($string, TRUE)); # eq. to NFKD()

       "$reordered_string  = reorder($string)"
           Reorders the combining characters and the like in the
           canonical ordering and returns the result.



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           E.g., when you have a list of NFD/NFKD strings, you
           can get the concatenated NFD/NFKD string from them,
           saying

               $concat_NFD  = reorder(join '', @NFD_strings);
               $concat_NFKD = reorder(join '', @NFKD_strings);

       "$composed_string   = compose($string)"
           Returns the string where composable pairs are com-
           posed.

           E.g., when you have a NFD/NFKD string, you can get its
           NFC/NFKC string, saying

               $NFC_string  = compose($NFD_string);
               $NFKC_string = compose($NFKD_string);

       Quick Check

       (see Annex 8, UAX #15; and DerivedNormalizationProps.txt)

       The following functions check whether the string is in
       that normalization form.

       The result returned will be:

           YES     The string is in that normalization form.
           NO      The string is not in that normalization form.
           MAYBE   Dubious. Maybe yes, maybe no.

       "$result = checkNFD($string)"
           returns "YES" (1) or "NO" ("empty string").

       "$result = checkNFC($string)"
           returns "YES" (1), "NO" ("empty string"), or "MAYBE"
           ("undef").

       "$result = checkNFKD($string)"
           returns "YES" (1) or "NO" ("empty string").

       "$result = checkNFKC($string)"
           returns "YES" (1), "NO" ("empty string"), or "MAYBE"
           ("undef").

       "$result = checkFCD($string)"
           returns "YES" (1) or "NO" ("empty string").

       "$result = checkFCC($string)"
           returns "YES" (1), "NO" ("empty string"), or "MAYBE"
           ("undef").

           If a string is not in FCD, it must not be in FCC.  So
           "checkFCC($not_FCD_string)" should return "NO".




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       "$result = check($form_name, $string)"
           returns "YES" (1), "NO" ("empty string"), or "MAYBE"
           ("undef").

           $form_name is alike to that for "normalize()".

       Note

       In the cases of NFD, NFKD, and FCD, the answer must be
       either "YES" or "NO". The answer "MAYBE" may be returned
       in the cases of NFC, NFKC, and FCC.

       A "MAYBE" string should contain at least one combining
       character or the like. For example, "COMBINING ACUTE
       ACCENT" has the MAYBE_NFC/MAYBE_NFKC property.

       Both "checkNFC("A\N{COMBINING ACUTE ACCENT}")" and "check-
       NFC("B\N{COMBINING ACUTE ACCENT}")" will return "MAYBE".
       "A\N{COMBINING ACUTE ACCENT}" is not in NFC (its NFC is
       "\N{LATIN CAPITAL LETTER A WITH ACUTE}"), while "B\N{COM-
       BINING ACUTE ACCENT}" is in NFC.

       If you want to check exactly, compare the string with its
       NFC/NFKC/FCC; i.e.,

           $string eq NFC($string)    # thorough than checkNFC($string)
           $string eq NFKC($string)   # thorough than checkNFKC($string)
           $string eq FCC($string)    # thorough than checkFCC($string)

       Character Data

       These functions are interface of character data used
       internally.  If you want only to get Unicode normalization
       forms, you don't need call them yourself.

       "$canonical_decomposed = getCanon($codepoint)"
           If the character of the specified codepoint is canoni-
           cally decomposable (including Hangul Syllables),
           returns the completely decomposed string canonically
           equivalent to it.

           If it is not decomposable, returns "undef".

       "$compatibility_decomposed = getCompat($codepoint)"
           If the character of the specified codepoint is compat-
           ibility decomposable (including Hangul Syllables),
           returns the completely decomposed string compatibility
           equivalent to it.

           If it is not decomposable, returns "undef".

       "$codepoint_composite = getComposite($codepoint_here,
       $code- point_next)"
           If two characters here and next (as codepoints) are



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           composable (including Hangul Jamo/Syllables and Compo-
           sition Exclusions), returns the codepoint of the com-
           posite.

           If they are not composable, returns "undef".

       "$combining_class = getCombinClass($codepoint)"
           Returns the combining class of the character as an
           integer.

       "$is_exclusion = isExclusion($codepoint)"
           Returns a boolean whether the character of the speci-
           fied codepoint is a composition exclusion.

       "$is_singleton = isSingleton($codepoint)"
           Returns a boolean whether the character of the speci-
           fied codepoint is a singleton.

       "$is_non_starter_decomposition = isNonStDecomp($code-
       point)"
           Returns a boolean whether the canonical decomposition
           of the character of the specified codepoint is a Non-
           Starter Decomposition.

       "$may_be_composed_with_prev_char = isComp2nd($codepoint)"
           Returns a boolean whether the character of the speci-
           fied codepoint may be composed with the previous one
           in a certain composition (including Hangul Composi-
           tions, but excluding Composition Exclusions and Non-
           Starter Decompositions).

       EXPORT

       "NFC", "NFD", "NFKC", "NFKD": by default.

       "normalize" and other some functions: on request.

AUTHOR
       SADAHIRO Tomoyuki <SADAHIROATcpan.org>

         http://homepage1.nifty.com/nomenclator/perl/

         Copyright(C) 2001-2004, SADAHIRO Tomoyuki. Japan. All rights reserved.

         This module is free software; you can redistribute it
         and/or modify it under the same terms as Perl itself.

SEE ALSO
       http://www.unicode.org/reports/tr15/
           Unicode Normalization Forms - UAX #15

       http://www.unicode.org/Public/UNIDATA/DerivedNormaliza-
       tion- Props.txt
           Derived Normalization Properties



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ext::Unicode::NorPerlzPrograemxmte:r:sUnRiecfoede::Normalize::Normalize(3p)


       http://www.unicode.org/notes/tn5/
           Canonical Equivalence in Applications - UTN #5























































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